Union all select distinct prof from professor order by l_name
l_ name
union . intersect [all] except [all], ( ).
49 , , , , ,
select l_name from student
intersect select prof from professor order by l_name
l_ name
79 () ( ).
80 () ( intersect), , , - .
, . , . , , . create view:
create view < > as <SQL-3anpoc>
50 , , - , :
create view analysis as select stud_nomer, dat, res from ball where dis = ''
, , : . SQL, , order by . SQL-: . - , as.
51 , :
create view avg_ball as select stud_nomer, avg(res) as avg_res from ball group by stud_nomer
avg_ball ,, : stud_nomer avg_res. , :
select * from avg_ball
stud nomer | avg_ res |
010001 | 85 |
010002 | 66 |
011003 | 63 |
011004 | 63 |
011005 | 16 |
ball avg_ball.
, .
81 () , ( , , ).
82 () , , , , ,
|
|
1_ | f name | position | additional | |
1 | ||||
.-. |
. select , , . , , SQL :
select max(avg_res)..
from avg_ball
:
select max(avg(res)) from ball group by stud_nomer
, SQL .
52 (5) :
select max(avg_res)
from (select avg(res) as avg_res
from ball
group by stud_nomer)
To , from SQL , .
83 () . , , .
84 () , . , .
85 (CD) . , -, .
86 (CD) . , ,., - ( ).
4 .